The Sinclair swine melanoma tumor system is an animal model of spontaneous malignant disease that has many features in common with its human counterpart. This model is being utilized to study the relationship between melanoma-associated antigens and tumor development, growth and regression. The objective of this proposal is to identify, isolate and evaluate melanoma-associated antigens present on primary cutaneous and metastatic melanomas. The approach used in this study is to identify and profile antigens associated with various swine cutaneous melanomas by in vitro serologic analyses with xenoantisera and monoclonal antibodies. Isolation and characterization of melanoma-associated antigens will be accomplished by affinity chromotography procedures and radioisotopic polyacrylamide gel electrophoreses.